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Orchard growers have long known that getting the maximum quantity and quality of fruit is based, in part, on the size and shape of the trees. Strategic hedging and topping exposes each tree to maximum sunlight and moisture, at the same time discouraging disease. Hedging helps maintain distances between rows so that equipment can be used in orchards without damaging the trees, whereas topping keeps trees from growing too tall to harvest.
To help growers maintain trees in their orchards at the optimum width and height, TOL Inc., Tulare, Calif., developed the TH1100 combination hedger/topper. Trimming trees has never been easier or faster. The TH1100 can cut both large and small citrus and deciduous trees, with the ability to maneuver in tight orchards over a wide variety of ground conditions.
Five large-diameter saws arranged at the end of individual arms on a star wheel (the star-shaped structure containing the saws) slice off unwanted brush, and the arms themselves help transfer the material away from the tops of trees, allowing it to fall in between rows. It ultimately improves crop yield, while preventing trees from reaching heights that are beyond the reach of human pickers.
Hydraulics plays a key role in virtually every operating function of the TH1100. It is powered by a 100-hp John Deere 4045T turbocharged engine driving an Eaton model 76 hydrostatic transmission. A gear pump provides hydraulic power for auxiliary functions: tower lift cylinder, horizontal-to-vertical positioning cylinder, cutting star swing cylinder, cutting star leveling cylinder, and engine hood lift cylinder.
Rotation of the star wheel is driven by an Eaton 2000 series low-speed, high-torque Geroler motor driven by an Eaton variable-displacement piston pump. The variable-displacement pump gives the operator precise rotational speed control for rotating the star wheel to position saw blades that are needed.
All of the machine’s hydraulic functions can be controlled from within the operator’s cab. Feedback from customers showed that they wanted the latest in hydraulics and simpler operation than in other machines—features TOL engineers made sure they incorporated into the TH1100.
Heavy-duty cylinders ranging in bore size from 1½ to 6 in. are standard throughout, operating with a maximum pressure of 2,000 psi. The SAE 100 R2 hose used is rated well above the TH1100-L’s maximum pressure to ensure long life and trouble-free operation. The hose is carefully routed to minimize damage from the surrounding brush.
Competing models are sickle-bar-type hedgers, which incorporate different concepts and are unable to cut very thick wood. The TH1100-L can handle wood up to 3 in. in diameter, but an experienced operator will be able to cut thicker wood with the machine. TOL has topper/hedgers operating in many countries, including the U.S., Canada, and Mexico.